Topic: Have a knock

[jbreshears]

I have a 90 wrangler with a 2.5 and it makes a knocking noise after it warms up a bit and i have no idea what the hell it is. I'm new to this so be easy please. Any help would greatly be appreciated

[dexetr30]

I have a 90 wrangler with a 2.5 and it makes a knocking noise after it warms up a bit and i have no idea what the hell it is. I'm new to this so be easy please. Any help would greatly be appreciated

Check the bolts on the exhaust manifold. Broken manifold bolts are a common cause of knock in these engines.

[Bounty Hunter]

Try 1/2 to 1 qt of automatic tranny fluid in the oil, see if it quiets it down.  Sounds like it may be a noisy lifter.

You can use a prybar or long wooden dowel to pinpoint sounds from the engine.  With the engine running, carefully place one end to different parts of the engine, your ear to the other end.  Works very well.

[oldjeep]

In mine it was a sticky lifter.  They cost $4 each, and you'll need to buy or rent a lifter remover.

[Desert Bob]

Mine was a sticky lifter as well.  I ordered the Lifters ($3.50 each) and the removal tool from Summit Racing.  The entire package, with assembly lube, was around $60 shipped to my door.  Took me better part of a day as Cylinder #4 Exhaust lifter was a royal pain to get back in.  Had to move the Map Sensor bracket and stand over the engine to get the right angle.  Sounds real nice now.

[Jeffy]

I have a 90 wrangler with a 2.5 and it makes a knocking noise after it warms up a bit and i have no idea what the hell it is. I'm new to this so be easy please. Any help would greatly be appreciated

Is it an actual knock you can feel or is it a tap that you can only hear?  Is it high up in the engine or low down?  If you're new to Jeeps then it would be just the normal noise, too.  2.5L's and 4.0L's are noisy compared to most other modern engines.